import org.omg.CosNaming.NamingContextExtPackage.StringNameHelper;

import java.util.HashMap;

/**
 * 学习HashMap源码
 *
 * @author wangxiyue@cyou-inc.com
 * @date 2019-07-27 18:47
 * @since 1.0.0
 */
public class Main {

    public static void main(String[] args) {
        System.out.println("new HashMap..");

        HashMap<String, String> hashMap = new HashMap();
        hashMap.put(null, null);
        String s = hashMap.get("1");
        System.out.println(s);
        hashMap.containsKey("1");
    }

}
